1. Field of Invention
In one aspect, this invention relates to hydraulic systems. In a further aspect, this invention relates to valves for hydraulic system.
2. Prior Art
Hydraulic valves are well known in the art. They provide safe positive flow of hydraulic fluid from a prime mover to various hydraulic devices. It is desirable under certain conditions to have a hydraulic drive system which powers a wheeled or tracked vehicle. Such drive systems must have a differential mechanism to allow different drive rates when the driven vehicle turns a corner. It would be desirable to provide the hydraulic system with a valve which can provide differential driving forces to opposite sides of the vehicle when the vehicle turns a corner.